Apparatus for coating the inner walls of bulbs



J. J. MALLOY Feb. 11, 1947.

APPARATUS FOR COATING THE INNER WALLS OF BULBS Filed Nov. 16, 1943 3 Sheets-Sheet 1 Invervbor John J. MELLOS,

Feb. 11, 1947. J. J. MALLOY 2,415,512

APPARATUS FOR COATING THE INNER WALLS OF BULBS Filed Nov. 16, 1943 s Sheets-Sheei'. 2

lnven'tow- John J. MaLLo ,Mvrn/ His Attor neg.

Feb. 11, 1947. J. J. MALLQY 2,415,512

APPARATUS FOR comma THE mma WALLS OF BULBS Filed Nov. 16, 1943 3 Shets-$heet s lnverfiror: John J. MGLLOH,

His A'htornes.

Patented Feb. 11, 1947 APPARATUS FOR COATING THE INNER WALLS F BULBS John J. Malloy, Cleveland Heights, Ohio, asslgnor to General Electric Company, a corporation of New York Application November 16, 1943, Serial No. 510,483

1 My invention relates toapparatus for applying coatings to the interior of tubular bodies such as the bulbs for fluorescent and incandescent lamps and more particularly to automatic apparatus for applying a coating of fluorescent material to the inner surface of the relatively long tubular bulbs of fluorescent lamps.

- The application of coatings to the bulbs of the usual commercial forms of fluorescent and incandescent lamps must be performed economically and as practically as possible, but still must be subject to extremely fine control to assure a coating of uniformly satisfactory and eflicient operation characteristics in successive bulbs. The control must, for instance, permit the application of a coating of very definite thickness, permit the distribution of the coating over the full length of the bulb and must avoid the formation of striations and other visual irregularities in any part of the bulb. The coating is in the form of a free flowing liquid suspension at the time of application and is preferably applied to the top end of the bulb so as to flow down over the walls to all parts of the bulb. A considerable excess of the coating fluid is released to the bulb to assure a positive movement of said fluid over the entire inner surface thereof and it drains out the open lower end of said bulbfi The viscosity of the coating fluid and the rate of drying determines to a great extent the thickness and distribution of the coating on the bulb.

One object of my invention is to provide apparatus for coating lamp bulbs automatically in a satisfactory and desirable manner. Automatically operating apparatus provides the advantages of the exact duplication of all operations and accuracy of control which produces a precise and uniform coating that is not possible on a commercial scale of production by other methods of operation.

Another object of my invention is to provide apparatus for flushing the coating fluid onto the walls of tubular bulbs in a satisfactory and practical manner. The apparatus provides for the introduction of coating material evenly over all portions of the walls of the bulb andis suchas to prevent contamination and dried particles of the coating material from being absorbed by the main body thereof and in due course carried into the coating placed on a. bulb.

Still another object of my invention is to provide in combiantion automatic apparatus for introducing coating'material rapidly into a succession of bulbs and conveying apparatus for presenting the bulbs at a definite position with rela- 21 Claims. (Cl. Ell- 43) tion to the coating apparatus and thereafter to drying means. The combination of such apparatus reduces the manual steps of the entire coating operation to'the insertion and removal of the bulbs from the conveying apparatus and the inspection of said bulbs. The advantages of such operations are both in providing a definite and uniform coating on the bulbs and the elimination of manual handling and are difficult and desirable inasmuch as said bulbs are often over two inches in diameter and five feet in length.

Other objects and advantages of my invention will appear in the detailed descriptionwhich follows of a species thereof shown in the drawings.

vIn the drawin ig. 1 is a diagrammatic plan view of apparatus of my invention for coating tubular fluorescent lamp bulbs on the inside wherein the apparatus outside of the enclosure thereof is shown to scale; Fig. 2 is a vertical section through the loading and unloading turret and bulb conveyor along line 2-2 of Fig. 1; Fig. 3 is a plan view of one head of the bulb-conveyor; Fig. 4 i a vertical section through one-half of the bulb coating turret and associated portion of bulb conveyor alongline i@ of Fig. 1; Fig. 5 is a vertical section on a larger scale through one of theoutlet nozzles of the coating apparatus midway in its period of operation; Fig. 6 is a side elevation of the conveyor head supporting rail and head repositioning cam at one side of the bulb coating turret; Fig. 7 is a perspective-view of the control finger of the nozzle actuating means; Fig. 8 is a perspective view of the actuat ing means for one of the nozzles; Fig. 9 is a side elevation of the agitator operating means for the header tank and the nozzle operating cam; and

Fig. 10 is schematic drawing of the coating fluid circulating system of my apparatus.

The species of my apparatus disclosed in' the drawings is necessarily large and extensive since it provides both for the coating of bulbs for fluorescent lamps which may be over two inches in diameter and five feet in length and the drying of said coating without manual handling in a continuous inline type, of operation. The bulbs l5 (Figs. 1 and 2) are manually loaded into the heads I6 of an endless belt type conveyor ll during the course of movement thereof about the loading and unloading turret l8 and are automatically coated on the inside'during the subsequent travel of the heads l6 about the turret IQ of the coating apparatus. Succeeding movements of the heads l6 carry the bulbs l5 back and forth in substantially parallel paths 20 to 21 inclusive within the enclosure 28 during which the coating dries to a condition where it can not be readily injured in the handling of the bulb in subsequent manufacturing operations. At one speed of operation a period of twenty minutes lapses between the time the bulbs l5 are inserted in the head l6 and the time they emerge from the enclosure '28 at a point adjacent the loading 1 and unloading turret l8 where they are removed from the apparatus. g

The insertion of the bulb |5 into the head l6 of the conveyor consists in pushing saidbulb vl5 between the fingers of the spring clip 29 (Figs.

tically disposed channel shaped slide 32 (Figs. 3

and 4) supporting the springelip 29 and rests 36, and a channel shaped support 33 attached to the conveyor chain 34 providing ways for the slide 32. The heads l6 are mounted at regular intervals l along the conveyor chain 34- which is directed along the desired paths of movement by various sprockets at spaced locations within the appara- "tus and at the loading station passes about the -;.sprocket 35.

'and heads '16 at this location is supported by the sprocket 35 which is fastened to the hub 36 on the idler shaft 31 which, in turn, is mounted in ,the bearings 38 and 39 within the yoke 40 mounted on a pedestal. (only partially shown) and the frame 42 (also only partially shown) of the enclosure 28. The lower end of the head I6 is 1 kept frompbeing pushed from its position directly below the upper end thereof during the "loading of the bulb |5 by being present in a notch inthe periphery of the spider 43, and by the en- The full weight of the chain 34 gagement of the roller 44 on the pin 45 held by bracket 46 with the guide rail 41. The bracket 48 and standard 49 and similar brackets and standards along the length of the guide rail 41', which extends along the entire path of movement of, the conveyor H, are themeans of supporting said rail 41 from the base (not shown) of the apparatus.

' The weight of the slide 32 of the head I 6 is normally, suflicient to cause it to remain in its lowered position within the channel of the support 33,.at which position the stud 50 extending from the back of'the slide 32 rests at the base of a longitudinal slot 5| (Fig. 4) in the support 33.

I However, the slide 32, during the course of movement of the head I 6 about the loading turret |8, is held down in position by the presence of the fiat cam 52 extending from the yoke 40 over the roller-'53 on theend of the stud 50. The insertion of the bulb 15 can not disturb the position of any part of the head l6 although considerable pressure is exerted in pushing the bulb l5 into the head l6 and adjustingit up into the proper position against the stop 3|. Support for the stop 3|is provided in the enclosure 28 (Fig. 1) and the standard 54, to the latter of which it is attached by means of the arm 55.

The motion of the conveyor I! which is 2 brought about-[through motion of the chain 34 is constant and carries the heads I 5 through the loading positions and thence along a straight path into the enclosure 28 and around a sprocket (not shown) on the shaft 55. In the course of this movement, the weight of the heads l5 of the conveyor istransferred from the sprocket 35 to a stationary bar or rail. (indicated at 51, Fig. 2) onto which the roller 58 on the support 33 is carried. A corresponding bar 59 (Fig. 6) extends along the succeeding course of travel of the conveyor I! which advances it from engagement with the sprocket on the shaft 56 to the coating turret 9 where the chain 34 passes onto the sprocket (Fig. 4). As shown in Fig. 6, the conveyor I"! is also guided along this course of movement by the rail 41 which engages the roller 44 on the lower part of the head Hi.

The movement of the conveyor heads 16 into engagement with the coating turret l9 advances the bulbs |5 into position below the outlet nozzles 60 (Fig. 4) in the bottom of the header tank 6| of the coating apparatus which nozzles 60 provide both for the release of the coating fluid from the tank 6| and the distribution of said fluid over the inner walls of the bulb I5. The support for the conveyor heads I6 in the coating turret I9 corresponds closely to that of the loading and unloading turret H3 in that the chain 34 of the 43' which passes about a portion of said head I6.

,The hub 36 and notched spider 43' are mounted at spaced points along the idler shaft 31 which is supported by the bearings 38 and 39' carried by the upper and lower parts of the yoke (only partially shown). The yoke 40', in turn. is mounted on a pedestal 4| and attached to a portion of the enclosure 28 as in the turret l8 although not completely shown in this connection.

The nozzles and header tank 6| have a course and speed of movement coresponding to the heads l6 as the tank 6| is mounted on the plate 62 carried by the extending portion 63 of the hub 36 holding sprocket 35' and provide an outlet for the coating fluid over the regularly spaced positions taken by the heads l6 of the conveyor When the conveyor |l advances into the immediate vicinity of the coating turret I9, the upper end of the bulbs l5 are below the plane of all parts of the nozzle 60 but as these paths converge, the roller 53 of the conveyor head l6 passes into a channel in the cam 64 (Fig. 6) causing the movable slide 32 and bulb IE to be raised. This motion of the bulb l5 carries the top end thereof up about the nozzle 66 to a point where the shoulder 65 (Figs. 4 and 5) on said end is against the angular face of three pins 66 extending from spaced points on the collar 61 and positions the bulb |5 both vertically and centrally with respect to the nozzle 60. The vertical motion is excessive and causes the clip 29 and the rests 30 to slide up along the bulb |5 very slightly. At the limit motion the roller 53 is carried over onto the straight section 64' of the cam-64 which extends around the turret l9 to a corresponding point on the opposite side thereof. Both portions of the cam 64 are supported by a plurality of arms of the bracket 68 (Fig. 4) which is attached to a flange on the upper arm of the yoke 40.

The succeeding steps in the operation of the apparatus occur when the conveyorhead |6 advances the bulb |5 into engagement with the curved shoe 69 of the control finger 16 (Figs. 1, 4 and 7) at which time said finger 10 places the nozzle opening means H mounted above the header tank 6| in condition to be effective. In instances where a bulb I5 is not carried by the head l6 and not engaged by the shoe 69, the finger 10 which is fastened to a pin 12 pivoted in the bracket I8 on the standard 54 (Fig. 1) will swing to a position nearer the center of the coating turret I9 because of the biasing effect of the spring 14 and will have no effect on the inoperative condition of the nozzle opening means II. At this limit of motion the branch 15 of the finger I8 rests against the stop nut I6 on the pin 'II extending from the bracket I8. However if the shoe 69 engages a bulb I5, the finger I8 will be farther outward from the center of the coating turret I9 than otherwise and the roller I8 will be in the path of movement of the lower end of' the push rod 19 of the nozzle opening means II and will lift said push rod I9 to a different position in the course of rotation of the coating turret I9. The effect of this operation is to turn the lever 88 (Figs. 4 and 8) of the nozzle opening means II to which the push rod I9 is attached by pin 8I so that the wedge 82, which is attached to said lever 88 by pin 88, is moved longitudinally and the thicker portion thereof is placed over the upper end of the metering pin 88 of the nozzle 88. With the wedge 82 in this position, the al-' most immediate downward movement of the arm 85 which is pivoted on the pin 86 held by bracket 8! and which now engages the cam 88 through roller 89 carries the screw 98 against said wedge 82 causing the said wedge 82 and metering pin 84 to move downward an amount required to produce the desired flow of coating fluid from the nozzle 88 to the bulb I5. The pull of the contraction force of the spring SI which extends between posts in adjacent pairs of push rods I9 and the friction produced between the screw 98 and the wedge 82 are sufficient to hold said rod 19 and the wedge 82 in place after the lower end of the push rod I9 passes beyond the vroller I8 of the control finger I8.

In instances when a bulb I5 is not held by the head I8, the movement of the arm 85 will be of no consequence as the wedge 82 will have remained in its original position where the thinner portion 92 is over the upper end of the metering pin 84 and sufficient clearance is provided for the full movement of the screw 98. At such times the lower end of the push rod I9 passes to one side of the roller I8.

The nozzle opening means II retains its relation with the nozzle 88 during the rotation of the turret I9 as it is mounted on the circular plate 93 covering the outer portion of the open top of the header -tank- 6I which plate 98 is supported on a plurality of posts 98 extending upward from the edge of the plate 62. The brackets 81 of each of the nozzle operating means II are mounted on the plate 93 directly below the ring 95 supporting the cam 88 which ring 95 (Figs. 1, 4 and 9) is held in place by four studs 98 extending from the bars 91 and 98 in turn mounted on the standard 99 of the frame 42 (only partially shown) of the enclosure 28.

The flow of coating material to the lamp I5 from the nozzle 68 is controlled by the vertical adjustment of the metering pin 88 which extends up through the center of the orifice cap I 88, (Fig. 5), the guide I M and the orifice tube I82 of said nozzle 68 and the header tank BI to a second guide I83 (Fig. 4) opposite the operating means II therefor. The metering pin 88 is under the constant influence of a spring I84 located between a cap I85 on the upper end thereof and the guide I83 which is clamped tightly in an opening in the plate 93 by the nut I85. The expansion force of the spring I84 is suificient to keep the frusto-conical end portion I86 of the metering pin 88 up 'tight against the seat formed by lip I8I on the end of the orifice cap I88 and prevent any flow of the coating fluid from the header tank 6| during the greater period of rotation of the coating turret I8.

When the nozzle operating means II is actuated and the metering pin 88 is moved down, the coating material contained within the header tank GI flows through the orifice tube I82, which is clampedtightly in an opening in the bottom,

of the header tank BI and the plate 62 by the nut I87, the opening in the orifice cap I88 and over the conical and skirted portions I86 and I89 respectively of the metering pin 88 to the walls of the bulb I5. The coating material flows around the legs (three) of the guide I M which extend into notches in the end of the orifice tube I82 and pass in a uniform uninterrupted stream over the full periphery of the lower portions I88 and I89 of the metering pin 88 to the bulb I5 where it follows the inner wall thereof. Since the upper end of the bulb I5 is positioned by the engagement of the pins 66 on the collar 67 with the shoulder 65 thereof and said collar 81, in turn, is fastened to the orifice cap I88 of the nozzle 68 by screw H8, the flow of coating fluid directed by metering pin 88 will in every instance engage the walls of the bulb I5 at a definite point with relation to said shoulder 65 regardless of slight variations in the length of the reduced end portion III of the bulb I5. It is preferred that the coating fluid pass from the skirt I89 of the metering pin 88 which-is at fifteen degrees to the horizontal to the curved part of the reduced end portion III of the bulb I5 since the flow is then very smooth and free of bubbles. of parts is also preferred since the stream of coating fluid strikes a portion of the bulb I5 which is subsequently covered by the base of the finished lamp and is therefore concealed as the force of the stream often causes the resultant coating to be thinner where it strikes the walls of the bulb I5.

The quantity or dosage of the coating fluid introduced in each bulb I5 is controlled both through the vertical movement of the metering pin 88, which can be adjusted by turning the screw 98 of the operating means II in or out of arm 85, and through the period of time said metering pin 88 is held in the open position by the presence of the cam 88 over the arm 85. Normal operation procedure provides that the metering pin 88 have .185 inch of movement and that the cam 88 extend for sixty degrees of the rotation of the turret I9.

After the roller 89 passes from the end of cam 88, the contraction force of spring 89 extending between a portion of arm and a part of bracket 81 turns said arm 85 until the stop screw 98' on another part of said arm 85 engages the back of bracket 8'! so that the metering pin 88 can return to its closed position. The force with which the coating fluid is discharged into the bulb I5 is of no consequence as it is determined by the pressure head created by the height of the coating fluid in the header tank 6i and is kept constant by the automatic release of additional fluid from the pipe II2 (Fig. 10) to the header tank 8I.

During the entire course of operation of the apparatus each bulb I5 must receive a like application of the coating fluid in order that a uniform deposit of the finely divided fluorescent material, which is held in suspension therein, be applied in every instance. To this end, means are provided in the propeller I I3 for agitating the This relation.

coating fluid within the header tank to prevent settling out of the fluorescent materials. The propeller H3 which is fastened to the lower end of a shaft H4 passing up through the cover H5 over the header tank 6| takes a constant rotative motion through its connection with the supporting and operating means H6 (Fig. 9) and can be separated from said means H6 for cleaning by unscrewing the collar III of the coupling joining the flanges of the shaft I I4 and the shaft I I8 of said means H6. The rotative motion of the driving means II 6 originates in the electric motor H9 mounted onthe bracket I20 extending from the stationary. standard 99 of the enclosure 28 and is transferred to the driving shaft H8 through the belt I2I, the pulleys I22 and I23, 2. commercial form of speed reducer I24, the shaft I25 and the bevel gears I26 and I21. The bracket I28 on the top end of the standard 99 provides the support for the speed reducer I24 whereas the arm I29 which is attached toa portion of bracket I28 provides the support for the shafts H8 and I25.

Because of the relatively rapid rate with which the bulbs I5 are treated in the apparatus and consequent rapid use of the coating fluid, and the necessity of keeping the fluid level constant within the header tank 6I, automatic means are provided for supplying additional coating fluid to the header tank 6| from a storage tank I30 (Fig. located at a. convenient position to one side of the'apparatus. The coating fluid is drawn out of the storage tank I30 by the pipe I3I and forced through pipe I32, the screen I 33' of the filter I33,

pipe I34 to the inlet pipe H2 in the header tank 6| by a pump I35 and is released to the header tank 6| as required by the float controlled valve I36 which is connected in pipe I I2. Anexcess of the coating fluid is conducted to pipe I I2 by a this system so that a return pipe I31 is provided to carry any unused coating fluid back to the storage tank I30. The above piping system has the dual purpose of conducting the desired coating fluid to the header tank 6| and of circulating the coating fluid at all times so that the fluorescent material can not settle out during'moments when little of said fluid is required by said header tank GI. The coating fluid within the storage tank I30 is not subject to settling as it is agitated by the rotation of the paddle wheel I88 which is connected to the compressed air driven motor I39. After periods of operation it may be desirable to clean oflc any solid particles of the fluorescent material carried by the coating fluid from the screen I33 of the filter I33 to permit the full flow of said fluid through said filter. This operation is brought about by stopping the pump I35 so as to stop the fiow'of the coating fluid in the usual direction through the supply circuit and then to open the valve I40 connected to the drain pipe I4I so that the direction of movement of the coating fluid is reversed in said circuit and flushes the materials onthe screen of the filter through the valve I40 and pipe I to the storage tank I an or, if desired, to any other means to which the pipe Hi can be connected.

Normal operation of the coating apparatus closes the nozzle 60 before the coating fluid flows the full length of the bulb I5 but the interval the nozzle 60 is open is suiflciently long to allow a considerably larger quantity of the coating fluid than 'is required to enter the bulb IS. The coatingfiuid is flushed onto the inner walls of v the bulb I5 and flows down said walls in a flood which finally reaches the open bottom end thereof where it drains to the trough I42. At one point along the trough I42, which extends around the end of the coating turret I9 and along the succeeding path of movement of the bulb I5, the fluid passes from the bulb I5 in a sufllcient quantity to form a bubble over the lower end of said bulb I5 excepting that a jet of air from a pipe I43 mounted along the edge of the trough I42 is directed against said end to burst it. The presence of the bubble over the end of the bulb I5 appears to prevent the free circulation of air through said bulb I5 and is believed objectionable because of striations and other irregularities appearing in the coating when it is allowed to persist. The bubble only tends to form during the first period of drainage from the bulb I5 and does not tend to reappear after it passes from the eifective" range of the air jet.

The succeeding course of travel of theheads I6 of the conveyor I'I advances the roller 53 on the slide 32 thereof into a declining portion of the cam 64 which corresponds to that portion of said cam (shown in Fig. 6) on the opposite side of the coating turret I9 and causes the slide 32 and the bulb I5 to be lowered from operative relation to the nozzle 60. There is no interference of parts, therefore, as the course of movement of the heads I6 of the conveyor II separates from that of the turret I9 and passes along a straight path into the enclosure 28. The subsequent period of travel of the head I8 allows the bulb I5 to drain and the coating material to dry in an atmosphere relatively free of dirt and dust and preferably a few degrees above ambient temperature.

The course of travel of the conveyor II carries the bulbs I5 through an opening in the end wall of the enclosure 28 which is complete on the closure to a driving sprocket on shaft I44 which sprocket reverses its path of motion. During this interval the excess coating fluid within the bulb I5 drains out into the trough I42 which extends along this path 20 and which is inclined so that coating fluid received by it flows in the direction of movement of the bulb I5. Continued movement of the heads I6 of the conveyor I'I carries the bulb. I5 along path 2|, around idler sprockets on the shafts I45 and I46 and returns the conveyor I I to a second driven sprocket on the shaft I41 adjacent shaft I44. During these intervals, the bulb I5 drains to the wider portion I48 of the trough I42 which lies under the straight paths 20 and 2I and the branch I49 of the trough I42 which lies under the curved path of travel thereof. The coating fluid received by the wider portion I48 of the trough I 42 is relatively thick and inOt free flowing but is recoverable as it is washed down to the drain I50 at the lowermost end thereof by the flood of free flowing coating fluid passing through it from the trough I42 around the turret I9 and along the trough I42, so as not to be recoverable, is-

replaced by the controlled release of additional vehicle from the pipe I53 which is connected to a supply thereof. V

Succeeding movements of the carrier II advances the bulb I from a point opposite the driving sprocket on shaft ll'l along the straight path 23. to an idler sprocket on the shaft I54 where it reverses its direction of movement, and passes again to a driven sprocket on shaft I55. Still further movements of the conveyor I1 carry the bulb I5 along path 25, around idler sprockets on the shafts I55 and- I51, along path 26, around the driven sprocket on shaft I58 and along the path, 21, all of which are located within the. enclosure 28'and keep the bulb I5 within the confined atmosphere therein until the coating on said bulb I5 is comparatively dry. The enclosure 28 is sufliciently long to permit a relatively high rate of operation of the conveyor I1,

and consequently the entire apparatus, and completely encloses the single drive means of the apparatus which is connected to the driving shafts IM, Ml, I55 and I58. The rotative driving motion is imparted to these shafts I54, I51, I55 and I58 through a corresponding gear I59 on the upper end of each shaft and originates in an electric motor I60 which drives a gear IBI meshing with the two innermost gears I59 on shafts I51 and I55 through the shaft I52, bevel gears I65 and IM and shaft I65. The outermost gears I59 on shafts I I and I58 are driven through the gears I56 and I6! respectively from i the adjacent gears I59 on shaft M5 and I58 respectively.

It is usually preferred that air be circulated through the bulbs I5 whileth'ey are within the enclosure 28 to promote the drying of the coating although the force-of the circulated air must be relatively slight at certain times to prevent injury to said coating. In this particular instance, air conducting manifolds are mounted over paths 20, 2I, 26 and 21 in such a position as to direct various amounts of air down through the top end of the bulbs I5 during their course of movement therealong and means are provided for supplying air a few degrees above ambient temperature to saidmanifolds. No other means is required for controlling the circulation and temperature of air in the enclosure 28 although a duct I69 lying along the center of the floor thereof and having openings on opposite sides is provided to draw out the vehicle laden air to 'an exhaust stack I extending out the top of the enclosure 28 so as to prevent its escape to immediate vicinity of the apparatus. The controlled conditions within the enclosure 28 in one instance dries the coating on the inside of the bulb I5 to such an extent that it can be handledwithout injury and will remain dust-free although the bulb I5 has remained within the enclosure 28 only twenty minutes. At the end of the drying period the conveyor I'I carries the heads I5 ,through an opening in the end of the enclosure 28 to the loading and unloading turret I8 'where the bulb I5 is removed therefrom.

What I claim as new and desire to secure by LettersPatent of the United States is: r

1. Apparatus for coating the inner walls of comprised of a plurality of heads each adapted to hold a bulb in a. vertical position and means for advancing the heads into operative relation below the nozzles of the coating turret, thence along a portion of the rotative path of movement thereof and along an extended course of move- 5 ment, an enclosure about the,extended course of movementof the conveyor, andmeans for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fidid discharged by said nozzles and then to be dried in the atmosphere within the enclosure.

2. Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, and a plurality of outlet nozzles located in the bottom of said tank atregularly spaced points along a path about the axis of rotation thereof, a conveyor comprised of a plurality of heads each adapted to hold a bulb in a vertical position and means for advancingthe heads intooperative relation below the nozzles of the coating turret, thence along a Portion of the rotative path of movement thereof and along an extended course of movement, an enclosure about the extended course of movement of the conveyor, means attached to the coating turret and engaging the conveyor for causing the movement of said conveyor to rotate said turret so that the bulbs and nozzles retain the proper relation to each other and means for actuating the conveyor to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nozzles and then to be dried in the atmosphere within the enclosure.

3. Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, and a plurality of outlet nozzles located in the bottom of said tank at regularly spaced points along a path about the axis of rotation thereof, a conveyor comprised of a plurality of heads each with a vertically movable slide adapted to hold a bulb in a vertical position and means for advancing the heads to positions below the nozzles of the coating turret, thence along a, portion of the 1'0- 1 tative path of movement and along an extended course of movement, an enclosure about the extended course of movement of the conveyor, means for raising the slides of the conveyor heads for an interval during the period said heads are aligned with the outlet nozzles to carry the upper ends of the bulbs over the ends of said nozzles and means for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nozzles and then to be dried in the atmosphere withw in the enclosure.

4. Apparatus for coating the inner walls of tubular bulbs comprising a. coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, and a plurality of outlet nozzles located in the bottom of said tank at regularly spaced points along a path about the axis of rotation thereof, a conveyor, for advancing said bulbs into operative relation below the nozzles of the coating turret, thence along a portion of the rotative path of movement thereof and along an extended course of movement,

comprised of a chain, and a plurality of heads each having a vertically movable slide for holding a bulb in a. vertical position, a support attached to the chain providing ways for and means of retaining said slide, means extending from the slide for permitting the adjustment thereof, a stationary cam mounted below the coating turret for engaging and raising the slide adjusting means of the heads to lift the slides and carry the upper ends of the bulbs over the ends of said nozzles, an enclosure about the extended course of movement of the conveyor and means for causing movement of the conveyor and corresponding motion in the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nomles and then to be dried in the atmosphere within the enclosure. 5. Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about avertical axis for holding a coating fluid, a plurality of outlet nozzles located in the bottom of said tank at regularly spaced points along a path about the axis of rotation thereof, and means mounted adjacent the nozzles for positioning the end of the bulb with respect thereto, a conveyor comprised of a plurality of heads each adaptedto hold a bulb in a vertical position and adjust the position of said bulb vertically and means for advancing the heads to positions below the nozzles of the coating turret, thence along a portion of the rotative path of movementthereof and along an extended courseof movement, an enclosure about the extended course of movement of the conveyor, means located adjacent the coating turret for causing the heads to raise the bulbs to carry the upper ends thereof over the ends of the nozzles and into engagement with the positioning means and means for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nozzles and then to be dried in the atmosphere within the enclosure.

6. Apparatus for coating the inner walls of tubular bulbs having reduced shouldered ends comprising a coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, a plurality of outlet nozzles located in the bottom of said tank at regularly spaced points along a path about the axis of ro tation thereof and a plurality of pins having angular faces mounted about the nozzles adapted to engage the shoulders on the ends of the bulbs to position them with respect to the nozzles, a conveyor comprised of a plurality of heads each adapted to hold a bulb in a vertical position and adjust the position of said bulb vertically and means for advancing the heads to positions below the nozzles of the coating turret, thence along a portion of the rotative pathof movement thereof and along an extended course of movement, an enclosure about the extended course of movement of the conveyor, means located adjacent the coating turret for causing the heads to raise the bulbs to carry the upper ends thereof over the ends of the nozzles and the shoulders of said bulbs into engagement with the angular faces of the pins to place the said bulbs in operative relation to the nozzles, and means for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nozzles and then to be dried in the atmosphere within the enclosure.

'7. Apparatus for coating the inner walls of tubular bulbs comprising a bulb loading and unloading turret, a coating turret located adjacent the first-mentioned turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, and a plurality of outlet nozzles located in the bottom of said tank at regularly spaced points along a path about the. axis of rotation thereof, a conveyor comprised of a plurality of heads each adapted to hold a bulb in a vertical position and means foradvancing the heads around a portion of the loading and unloading turret, thence into relationbelow the nozzles of the coating turret and along a course of movement therebetween. an enclosure about said course of movement for drying the coated bulbs, and means for actuating the conveyor and rotating the loading and unloading, and coating turrets. v V

8. Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, and a plurality of outlet nozzles located tank at regularly spaced points along a path about the axis of rotation thereof, a conveyor for advancing said bulbs into operative relation below the nozzles of the coating turret, thence along a portion of the rotative path of movement thereof and along an extended course of movement, comprised of a chain, and a plurality of heads each having means for holding a bulb in a vertical position and rollers attached to the holding means adapted to support and guide said holding means during movement of the conveyor, rails mounted along the path of movement of the conveyor about the coating turret and the extended course thereof engaging the rollers of the heads for keeping the heads to the same path ofmovement of the chain and for supporting said heads for at least a, portion of said movement, an enclosure about the extended course of movement of the conveyor, and means for causing movement of the conveyor and corresponding motion in the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharge by said nozzles and then to be dried in the atmosphere within the enclosure.

9. Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about a vertical axis for holding -a coating fluid, and a plurality of outlet nozzles located in the bottom of said tank at regularly spaced points along a path about the axis of rotation thereof, a conveyor comprised of a plurality of heads each adapted to hold a bulb in a vertical position and means for advancing the heads into operative relation below the nozzles of the coating turret, thence along a portion of the rotative path of movement thereof and along an extended course of movement, an enclosure about the extended course of movement of the conveyor, means for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nozzles and then to be dried in the atmosphere within the enclosure, a trough mounted below the path of movement of the heads about the coating turret and along the extended course of movement thereof and inclined downward from said turret for catching the excess coating fluid draining out of the bottom of the bulbs, and means connected to the lowermost portion of the trough along the course of movement of the heads for recovering and rein the bottom of said turning the excess coating fluid to the header tank. l

10. Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable abouta vertical axis for holdinga coating fluid, a plurality of outlet nozzles located mule bottom of the tank at regularly spaced points along a path about the axis of rotation thereof, metering pins extending'upward through the nozzles and through the header tank for controlling the flow of coating fluid through the nozzles, nozzle opening means engaging the upper ends of the metering pins for adjusting said pins to produce a flow of coating fluid from the nozzles during aportion of the rotation of the coating turret, a conveyor comprised of a plurality of heads each adapted to hold a bulb in a vertical position and means for advancing the head into operative relation below the nozzles of the coating turret, thence along a portion of the rotative path of movement thereof and along an extended course of movement; an enclosure about the extended course of movement of the conveyor and means for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nozzles and then to be dried in the atmosphere within the enclosure. a I

11.,Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, a plurality of outlet nozzles located in the bottom of the tank at regularly spaced points along a path about the axis of rotation thereof, metering pins extending upward through the nozzles and through the header tank for controlling through longitudinal motion the flow of the coating fluid through the nozzles, a guide for the metering pin mounted about the upper end portion thereof, means mounted adjacent the upper ends of the metering plurality of heads each adapted to hold a. bulb in a vertical position and means for advancing said bulbs into operative relation below the nozzles of the coating turret, thence along a, portion of the rotative path of movement thereof and along an extended course of movement, an enclosure about the extended course of movement of the conveyor and means for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nozzles and then to be dried in the atmosphere'within the enclosure.

12. Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about a vertical axisfor holding a coating fluid, a plurality of outlet nozzles located in the bottom of the tank at regularly spaced points along a path about the axis of rotation thereof, metering pins extending upward through the nozzles and through the header tank for controlling through longitudinal motion the flow of the coating fluid through the nozzles, guides for the metering pins mounted about the upper end portions thereof, means mounted adjacent the upper ends of the axis of rotation thereof, metering pins extending metering pins for normally holding said pins up in their closed position, nozzle opening means engaging the upper ends of the metering pins for adjusting-said pins downward to produce a flow of coating fluid from the nozzles during a portion of the rotation of the coating turret, a conveyor comprised of a plurality of heads each adapted to hold a-bulb in a vertical position,

means for advancing the headsfinto operative relation below the nozzles of the coating turret and then beyond the nozzles, and means engaging a bulb in a head of the conveyor in operative relation to an outlet nozzle for controlling the operation of the nozzle opening means to prevent the discharge of the coating fluid therefrom when a bulb is not in place about, said nozzle.

13. Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, a plurality of outlet nozzles located in the bottom of the tank at regularly spaced points along a path about the upward through the nozzles and through the header tank for controlling through longitudinal motion the flow of the coating fluid through the nozzles, guides for the metering pins mounted about the upper end portions thereof, spring means for normally holding said pins in the closed position, a stationary cam mounted over the header tank, and nozzle opening means located adjacent the upper ends of each of the metering pins and engaging thecam for adjusting said pins to produce a. flow of coating fluid through the nozzle corresponding to a diflerence in shape of the portion of the cam engaged thereby, a conveyor comprised of a plurality of heads each adapted to hold a bulb in a vertical position and means for advancing said bulbs into operative relation below the nozzles of the coating turret, along a portion of the rotative path of movement thereof and along an extended course of movement, an enclosure about the extended course of movement of the conveyor and means for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nozzles and then to be dried in the atmosphere within the enclosure.

14. Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, a plurality of outlet nozzles located in the bottom of the tank at regularly spaced points along a path about the axis of rotation thereof, metering pins extending upward through the nozzles and through the header tank for controlling through longitudinal motion the flow of the coating fluid through the nozzles, guides for the metering pins mounted about the upper end portions thereof, spring means for normally holding said metering pins up in their closed position, and nozzle opening means located adjacent the upper ends of each of the metering pins comprised of actuating means movable toward and away from the end of one of said pins but not in engagement therewith, a wedge movable to a position over the end of the metering pin so as to be engaged by said actuating means to move said pin downward and allow the coating fluid to pass from the nozzle, a con,- veyor comprised of a plurality of heads each adapted to hold a bulb in a vertical position, means for advancing the heads into operative relation below the nozzles of the coating turret and mit the nozzle actuating means to move the metering pin. 7

15. Apparatus for coating the inner walls of tubularbulbs comprising a coating turret comprised of a header tank rotatable about a, vertical axis'forholding a coating fluid, a plurality of outlet nozzles located in the bottom of the tank at regularly spaced points along a path about the axis of rotation thereof, aconveyor comprised of a plurality of heads each adapted to hold a bulb in a vertical position and means for advancing said bulbs into operative relation below the nozzles of the coating turret, thence along a portion of the rotative path of movement thereof and along an extended course of movement, an enclosure about the extended course of movement of the conveyor, means for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the con veyor first to be flushed by coating fluid discharged by thenozzles'and then to be dried in the atmosphere within the enclosure, and means located below the coating turret for directing a jet of air at the stream of coatingfluid flowing out the end of the bulbs to prevent the formation of a bubble.

16(Apparatus for coating the inner walls of tubular bulbs comprising a coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, a plurality of outlet nozzles located in the bottom of the tank at regularly spaced points along a path about the axis of rotation thereof; metering pins extending upward through the header tank for controlling the flow of coating fluid through the nozzles, and nozzle opening means engaging the upper ends of .the metering pins for adjusting said pinsto produce a' flow of coating fluid from the nozzles during a portion of the rotation of the coating turret, a source of supply of the coating fluid, means for replenishing the coating fluid in the header tank from the source thereof as rapidly as it is used, a conveyor comprised of a plurality of heads each adapted to hold a bulb in a vertical position and means for advancing said bulbs intooperative relation below the nozzles of the coating turret, thence along a portion of the rotative path of movement thereof and along an extended course of movement, an enclosure about the extended course of movement of the conveyor and means ,for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharged by said nozzles and then to be dried in the atmosphere within the enclosure,

1'7. Apparatus for coating the inner walls of tubular bulbs having reduced shouldered ends comprisinga coating turret comprised of a header tank rotatable about a vertical axis for holding a coating fluid, a plurality of outlet nozzles located in the bottom of the tank at regularly spaced points along a, path about the axis of rotation thereof, means mounted adjacent the nozzles for engaging the shoulders on the ends a the bulbs to position them with respect to the heads for holding the bulbs in a vertical position,

means located adjacent the coating turret for raising the heads to carry the upper ends of the bulbs over the nozzles and the shoulders of said bulb against the positioning means, an enclosure about the extended course of movement of the conveyor, and means for actuating the conveyor and rotating the coating turret so as to cause the bulbs in succeeding heads of the conveyor first to be flushed by coating fluid discharge by said nozzles and then to be dried in the atmosphere within the enclosure. I

18. In apparatusof the class described for coating the interior surface of a tubular bulb, means for holding the bulb in a vertical position, means for flushing a sumcient quantity of coating liquid into the top of the bulb so that it flows down the walls thereof and drains out the bottom thereof in suflicient quantity to form a bubble over the lower end of the bulb, and means for directing a jet of air at the stream of coating liquid flowing from the bottom of the bulb to prevent the formation of such a bubble.

19. Apparatus of the class described for coating the interior of tubular .bulbs comprising a coating turret including a header tank rotatable about a vertical axis for holding a coating fluid, a plurality of outlet nozzles mounted on the bottom of the tank at regularly spaced points along a path about the axis of rotation thereof, metering pins extending upward through the nozzles and through the header tank for controlling the flow of coating fluid through the nozzles, means to support bulbs in vertical alignment with said nozzles and to carry them along with said nozzles during rotation of said header tank, and nozzle opening means engaging the upper ends of said metering pins for actuating said pins to produce a flow of coating fluid from the nozzles into the bulbs during a portion of the rotation of the coating turret, said nozzle openin means being constructed and arranged to hold said metering pins in open positionfor a, predetermined length of time to thereby permit delivery of a predetermined quantity of coating fluid into each bulb.

20. Apparatus of the class described for coating the interior of tubular bulbs comprising a coating turret including a, header tank rotatable about a vertical axis for holding a, coating fluid, a plurality of outlet nozzles mounted on the bottom of said tank at regularly spaced points along a circular path, metering pins extending upward through the nozzles and through saidtank and having flared heads at their lower ends for open-- ing and closing the nozzles and directing the flow of coating fluid therefrom, means to support bulbs in vertical alignment with said nozzles with their 17 mined time during a portion of the rotation of the coating turret,

21. In apparatus of the class described for coating the interior of a tubular bulb having a reduced shouldered end, a verticaly disposed dis- 5 charge nozzle for a coating liquid, support means for said nozzle, a metering pin extending verpin downward a predetermined amount to open said nozzle and carry the flared head portion of i8 the metering pin within the upper bulb end adjacent the shoulder thereon to a position at which the coating liquid is directed at said shoulder by said head portion of the metering pin.

1 JOHN J. MAILOY.

REFERENCES CITED The following references are of record in the m file of this patent:

UNITED STATES PATENTS Number Name Date 2,084,094 Kronquest, et a1. June 15, 1937 2,322,211 Albright June 22, 1943 2,324,455 Keim, et al July 13, 1943 1,782,450 Taylor Nov, 25, 1930 

